To using a digital suica vs physical card? iOS Digital suica can be set to express transit card mode so it can scan without unlocking the phone. Or even when iphone has turned itself off to conserve power "Power Reserve Mode" https://www.youtube.com/watch?v=hkhGGUZB7W0

You used to be able to recharge it from just about anywhere, anytime like when the yen is high and you're out of the country* and still can with foreign Amex and MC (Visa has issues). Domestic credit cards are also fine. There is a difference in that digital suica inactivation period is 6 months of non-use while IC card is 10 years. Recharging the digital suica will reactivate it or taking it to a staffed gate.

* ETA = I travel to the somewhat inaka and very inaka. Somewhat inaka - it is much easier to reload at my own convenience wherever I have data so I can still use it at a combini or later when I am inbound to a city with IC transit points (again, somewhat inaka). Fairly inaka, possibly unstaffed gate. Some unstaffed gates on commuter routes are getting suica tap posts vs paper only tickets with cash payment.

I keep my suica on an Apple Watch when in JP (does not support Reserve Power) so it is attached to my wrist. I'm a bit clumsy and find this easiest & safer for my phone & purse contents.

More info on setup https://www.youtube.com/watch?v=3n86ML7SgHM